Counter with novel drive mechanism



Jan. 14, 1969 F. P. KNOX 3,421,690

COUNTER WITH NOVEL DRIVE MECHANISM Filed July 21, 1967 aim/ United States Patent COUNTER WITH NOVEL DRIVE MECHANISM Francis P. Knox, Bloomfield, Conn., assignor to Redington Counters, Inc., Windsor, Conn., a corporation of Connecticut Filed July 21, 1967, Ser. No. 655,083

US. Cl. 235117 11 Claims Int. Cl. G06c 27/00; G06m 1/00 ABSTRACT OF THE DISCLOSURE There is provided a counter with a novel drive assembly comprising a combination including a pinion member cooperating both with a number wheel and with an oscillatable ratchet. The pinion member has two axial portions each with teeth spaced equidistantly about its circumference, the first portion having twice the number of teeth as the second. The first number wheel is in meshing engagement with the first portion of the pinion member and the ratchet is mounted for oscillation adjacent to the second portion of the pinion member. Biasing means urges the pinion member into driving engagement with the ratchet during oscillation thereof in a forward direction and urges the pinion member from driving engagement with the ratchet during oscillation thereof in the opposite direction. Means are also provided for controlling the motion input to the ratchet to minimize likelihood of injury to parts.

BACKGROUND OF THE INVENTION Counters are Widely employed in industry and elsewhere for recording various items of numerical significance including the operation of presses, attendees, etc. The input to the counting mechanism may be mechanical through oscillation of a suitable pivot arm or electrical or a combination of both electrical and mechanical actions. It is customary to employ a pinion which drives the first number wheel through meshing engagement with a tooth portion thereof and for this number wheel in turn to drive the remaining number wheels in a predetermined sequence.

One of the major sources of wear and tear in counters is the abruptness with which motion is imparted to the drive pinion through the drive mechanism and, over extended periods of time, breakdown in the drive mechanism may occur. In addition, sometimes complicated arrangements have been employed as a means of overcoming the tendency for the drive pinion to rotate in the reverse direction and thus nullifythe count just recorded.

It is a object of the present invention to provide a novel counter with a simple but highly effective drive mechanism capable of producing a relatively high degree of efiiciency and accuracy in operation.

It is also an object to provide such a counter which utilizes parts which may be produced relatively simply and inexpensively and may be assembled conveniently and quickly.

Another object is to provide such a counter which will permit both pretravel and overtravel of components for ease of count stroke adjustment.

SUMMARY OF THE INVENTION It has now been found that the foregoing and related objects can be readily obtained in a counter utilizing a drive mechanism which includes a rotatably mounted pinion member having a pair of axially adjacent portions each with a multiplicity of axially-extending teeth spaced equidistantly about the periphery thereof. One portion has twice the number of teeth as the second and the teeth of the second portion are aligned with alternate teeth of the first portion. A number wheel is rotatably mounted in meshing engagement with the first portion of the pinion Patented Jan. 14, 1969 ice member and a ratchet is oscillatably mounted adjacent to the pinion member with its axis of oscillation parallel to the axis of rotation thereof. The ratchet has a generally curvilinear edge surface which is slidable upon the teeth of the second portion of the pinion member, and the curvilinear edge surface is configured to engage the teeth thereof to cause rotation of the pinion member in the forward direction counter to the direction of oscillation of the ratchet.

Biasing means bears upon the pinion member to urge it against the curvilinear edge surface of the ratchet and also to urge its rotation in a direction counter to the forward direction of oscillation of the ratchet. This .is accomplished by positioning the biasing means so that it bears against a following edge of one of the teeth of the pinion member at all times when another of the teeth is not in driving engagement with the ratchet curvilinear edge surface. The positioning of the biasing means also allows it to bear against a following edge of one of the teeth for a period of time prior to disengagement of another tooth from the edge surface. The ratchet is designed to rotate the pinion member at least to a point where the biasing means bears against a following edge of a tooth of the pinion member. Means for oscillating the ratchet are also provided in the combination, and the drive assembly preferably includes means for controlling the input motion.

In accordance with a preferred embodiment of the invention, the ratchet is drivingly engaged by a driving member which is oscillatably mounted for oscillation about an axis parallel to the axis of the ratchet and is oscillated by an input which may be mechanical or electrical. Conveniently, the input effects direct oscillation of the shaft upon which the driving member is mounted. To provide a constant motion input, the drive connection comprises a pin and slot arrangement. One member, preferably the ratchet, is provided with a slot which has two portions, an elongated portion extending se-cantally outwardly and a relatively short portion which extends in a substantially radial direction from the outer edge of the elongated portion. The other member, preferably the driving member, has a stud or pin or boss which extends laterally therefrom at a point spaced from its axis into sliding engagement within the slot.

With such a drive arrangement, initially the stud is seated in the radial portion of the slot which is offset from a line drawn between the axes of the two members. As the driving member starts to oscillate, the stud moves radially toward the center of the ratchet because of the difference in radii with little motion, if any, of the ratchet to permit relatively free pretravel of the driving member. As the continued oscillatory motion of the driving member starts to move the ratchet, the stud enters the secantal portion of the slot which extends across the line between axes. By proper angular orientation and dimensioning of the secantal portion, the input motion can be rendered substantially constant by increasing the effective radial distance as the stud moves in the direction of the axis of the ratchet. The secantal slot portion can be of sufficient length to permit over travel of the stud therein and thus avoid abrupt motions.

Although the pinion member can be formed from two separate elements providing the two differently toothed portions thereof which are then engaged for simultaneous rotation, preferably it is integrally formed as a mutilated pinion by molding, casting or the like. The relative length of the short and long teeth in the two portions is not critical, but the peripheral spacing between teeth in the second portion should cooperate with the radius of the arc of the ratchet so as to provide a spacing therebetween through which the ratchet can pass unimpeded.

The teeth around the circumference of the pinion member need not be restricted to any particular number, but it should be appreciated that large numbers of teeth will tend to cause operation of the mechanism to be overly sensitive and subject to possible inaccuracy in the event of minor misalignment. The pinion member must have at least six teeth, i.e., three long and three short, because continuous rotation and proper relationships with the ratchet can not be established with fewer teeth. It has been found that a pinion having eight teeth operates very well because it provides efiicient movement without unduly complicating alignment and sensitivity of the mechanism. For proper operation the number of teeth utilized, the configuration of the ratchet and placement of the biasing means must be consistent and such configuration and placement will usually depend upon the selected design of the pinion and ratchet.

The pinion member is mounted for rotation upon a shaft which provides an axis of rotation parallel to the axis of the number wheel, and also parallel to the axes of oscillation of both the drive member and the ratchet.

Although the ratchet may have any generally curvilinear edge surface which will provide a shoulder for driving engagement with the pinion in one direction and slippage in the other direction of oscillation, the preferred con-figuration utilizes a recess in the edge surface to receive the pinion teeth and rotate the pinion through a portion of a revolution, after which the tooth is disengaged from the recess. It is important that the ratchet have a smooth surface bordering at least one side of the recess to allow relative sliding movement of the ratchet and pinion teeth and thus to prevent excessive rotation of the pinion member. Although the ratchet design may be varied greatly, it is necessary in all instances that its edge surface enter into driving engagement with only the long teeth of the pinion in the second portion or zone.

The biasing means bearing upon the pinion member generally serves two functions: (1) it forces the pinion member against the arcuate edge surface of the ratchet and (2) it urges rotation of the pinion member in a direction counter to the direction oscillation of the ratchet member. A flat spring fixed at one end to the frame of the counter and having its other end bearing tangentially against the zone or portion of the pinion having the reduced number of teeth has been found to serve this dual function simply and economically. With regard to the first requirement, any spring placement which will tend to force the pinion against the ratchet will be satisfactory. As to the second requirement, however, spring placement is critical to ensure that rotation of the pinion is urged by the spring in only one direction. This necessitates placement of the spring tangentially against the zone or portion of the pinion having the reduced number of teeth so that it can bear against the following edge of one tooth without also bearing against the leading edge of the next adjacent tooth, and thus counteract effective rotation in the desired single direction. It will be appreciated that the spacing between teeth in the second zone or portion of the pinion member facilitates this action and that limiting the total number of teeth positioned about the circumference is desirable. It is necessary that the spring bear upon the following edge of teeth of the pinion member at all times when another tooth of the pinion is not within the recess in the ratchet and also for a period prior to disengagement of a tooth from the recess.

The number wheels employed in the counter are conveniently of the type commonly used in such devices, having the numerical indicia inscribed on the circumferential surface thereof. The number wheel is mounted adjacent the mutilated pinion and in meshing engagement for rotation in cooperation therewith. A pinion releasably engageable with the number wheel will most desirably he provided at one side thereof to mesh with the Zone of the mutilated pinion which has the larger number of effective teeth, so that rotation of the mutilated pinion will rotate the wheel. The wheel pinion should generally be disengageable from the number wheel to allow 11'6- setting of the counting device. The number wheel will generally have, on the side opposite to the side'on which the wheel pinion is located, means such as a driving lug for engaging a transfer pinion which serves to rotate additional number wheels provided to increase the capacity of the counter. Limiting means is desirably provided to restrict the travel distance of the driving member so as to avoid overdrive and the consequent danger of injury to the parts of the mechanism. Such means can constitute a pair of wings on the driving member and a lug or boss projecting from the frame into the channel or recess between the wings. The travel distance is thereby restricted by the distance between the wings since the lug or boss will form an abutment limiting the oscillatory arc. Alternatively, a lug may be provided on the driving member which cooperates with a pair of projections on the frame to prevent overdrive in a similar fashion.

The counter mechanism components may be fabricated from metals, plastics, etc. The material used should, of course, be chosen to provide the maximum in efficiency and longevity to the device. From the standpoint of quietness and smoothness of operation, it is frequently found that plastics such asnylon and Delrin are well suited, and, of course, some portions of the device may be of metal and others of plastic depending upon the function of the particular element. It will be appreciated that the present invention is concerned primarily with the means by which oscillatory motion is converted into intermittent rotational motion and that the other portions of the counter mechanism may be conventional.

BRIEF DESCRIPTION OF THE DRAWING FIGURE 1 is a perspective view of a counter embodying the present invention;

FIGURE 2 is aside elevational view thereof to an enlarged scale with a portion of the cover broken away to show a portion of the drive mechanism;

FIGURE 3 is a partially diagrammatical view to an enlarged scale of the drive mechanism of the invention in the initial rest position;

FIGURE 4 is a similar view of the mechanism in a position after initiation of the counting cycle;

FIGURE 5 is a similar view of the mechanism at a later stage in the counting cycle;

FIGURE 6 is a similar view of the mechanism at the completion of one-half of the counting cycle; and

FIGURE 7 is an exploded view of the drive member and the ratchet in the drive mechanism.

DESCRIPTION OF THE ILLUSTRATED EMBODIMENT Turning now to the drawing in detail, FIGURES l and 2 illustrate a mechanical counter embodying the present invention and having a cover generally desingated by the numeral 10 with an opaque body portion 12 and a transparent viewing window 14 supported in the top wall thereof. The cover 10 is mounted on a frame, generally designated by the numeral 16, which has a flange 18 at the base thereof for mounting the assembly upon a supporting surface.

As seen in FIGURE 2, journalled in the end Walls 19 of the frame 16 is a shaft 26 upon which are rotatably mounted a multiplicity of number wheels 20 bearing numerical indicia on the circumferential surface thereof and viewable through the window 14 as they rotate into position underlying. A pivot arm 22 is mounted at one end on the shaft 28 and is the means for actuating the counting mechanism. A knurled knob 24 is provided on shaft 26 outwardly of the cover 10 to aid in resetting the number wheels 20.

As best seen in FIGUR-ES 2 to 7, the counting mechanism includes a mutilated pinion generally designated by the numerical 30- which has alternating around the circumference thereof a plurality of teeth 32 extending through the axial length thereof and teeth 34 extending axially only along a portion of the length thereof. Since the short teeth 34 are in alignment along one end of the pinion 30, they provide a first zone in which the number of teeth is twice that in the second zone provided at the other end solely by the long teeth 32. The mutilated pinion1'30 is rotably mounted at one end of a shaft 36 which is supportgd in brackets 37 adjacent the end of the frame 16 and held therein by spring clips 38.

A ratchet generally designated by the numeral 42 is mounted for oscillation upon the shaft 26 upon which the number wheels are also mounted. Inits periphery, the ratchet 42 has a recess 44 which is designed to receive a portion of the long teeth 32 and thereby to turn pinion as it oscillates upon the shaft 26. A flat spring afiixed to the frame 16 is positioned so as to bear tangentially against the pinion 30 and bias it toward the ratchet 42, the spring 40 bearing upon the second zone of the pinion 30 having the lesser number of teeth. A driving member generally designated by the numeral 46 is mounted for oscillation at the end of the shaft 28 adjacent the pinion 30 and ratchet 42 and serves to drive the ratchet 42 by engagement therewith as will be more fully pointed out hereinafter.

"As seen in FIGURE 2, the wheel gear 48 is positioned adjacent the side of the number wheel 20 for rotation upon. the shaft 26 by its meshing engagement with the mutilated pinion 34 on the side of the pinion 30 wherein the double number of teeth is located. The wheel gear 48 is disengageably connected to the number wheel 20 by conventional means (not shown) to allow resetting of the number wheels 20 by the resetting knob 24. Rotation of the pinion 30 causes rotation of the wheel gear 48 which in turn revolves the Wheel 20* to sequentially exhibit the indicia thereupon. Provided on the opposite side of the number wheel 20 is a transfer portion 50, which has a drive lug (not shown) at one point about its circumference. As the wheel 20 rotates, the drive lug will engage the transfer pinion 52 to advance the adjacent number wheel through a wheel pinion (not shown) similar to 48. Similar structure provides means for advancing the remaining several number wheels 20- in the desired sequence.

In FIGURES 3-6 there is diagrammatically illustrated the operation of the mechanism whereby the oscillatory motion of the pivot arm 22 and its actuating shaft 28 is converted into the rotary movement of the mutilated pinion 30 through the coupling of the driving member 46 to the ratchet 42. FIGURE 3 shows the mechanism in the initial rest position with a tooth 32 on the verge of entering the recess 44 of the ratchet 42 and with the flat spring 40 bearing against the following edge of another of the wide teeth designated 32'. This forces the pinion 30 against the arcuate edge surface 62 of the ratchet 42 and also urges rotation of the pinion 30'. As the ratchet 42 oscillates in a clockwise direction, the flat spring 40 urges the tooth 32 in a counter rotational direction and into the recess 44 provided in the arcuate edge surface 62.

FIGURE 4 illustrates the mechanism shown in FIG- URE 3 at a point in time after the oscillating ratchet 42 has turned in a forward direction through a small portion of a cycle. It will be seen that in this position the tooth 32 of the pinion 30 has been engaged in the recess 44 located in the arcuate edge surface 62. of the ratchet 42.

The continuing oscillation of the ratchet 42 to the position depicted in FIGURE 5 rotates the pinion 30 to a position just prior to expulsion of the tooth 32 from the recess 44. In this position another tooth 32" has overridden spring 40 and is in a position with respect thereto wherein the spring 40 imparts no rotational motion to the pinion 30. It will be apparent that continued oscillation of the ratchet 40 will position the other tooth 32" in a relationship with the spring 40 wherein the spring bears against a following edge of the tooth. Thus, the combination of the spring 40 and the ratchet 42 urging rotation of the pinion 30 causes expulsion of the tooth 32 from the recess 44 during the continued rotation of the ratchet 40 in response to the oscillatory movement of the driving member 46.

As the ratchet 42 completes the forward half of its cycle, the mechanism assumes the relationship depicted in FIGURE 6. Here, the tooth 32' is forced against the arcuate edge surface 62 under the influence of the flat spring 40 bearing upon a following edge of the tooth 32", and tooth 32, previously engaged with the recess 44, is wholly expelled therefrom. At this point, the drive shaft 28 and driving member 46 start the ratchet 42 oscillating in a reverse direction. As the ratchet 42 oscillates backward, the leading edge of the tooth 32 bears upon the arcuate edge surface 62 under the influence of a flat spring 40 bearing upon a following edge of the tooth 32". In this position, the ratchet 42 can return to the initial rest position depicted in FIGURE 3 without engaging the tooth 32 just expelled from the recess 44. Accordingly, cancellation of the count just recorded is prevented.

Shown in FIGURES 3-6 is a preferred embodiment of the invention wherein there is provided means limiting the arc of oscillation of the driving member 46. A pair of peripherally spaced wings 58 on the driving member 46 provide a channel 63 therebetween in which is received the abutment block 60 on the frame 16 so that oscillation of the driving member 46 is only through an arc until the block 60 abuts against the surface of one of the wings 58. Such a relationship protects the mechanism by preventing overdrive and undue strain on the component parts.

In FIGURE 7 is illustrated the preferred embodiment of engagement between the driving member 46 and the ratchet 42. As can be seen, the driving member 46 has a stud 56 projecting laterally therefrom at a point remote from axis of oscillation provided by the shaft 28. The stud 56 rides in a slot in the ratchet 42 generally designated by the numeral 54 which has an elongated portion 64 extending secantally outwardly from the axis thereof. The slot 54 also includes short, substantially radially outwardly extending portion 66 at the outer end thereof. Utilization of such a design allows controlled acceleration of the ratchet and minimizes impact, which thereby improves the drive action and provides longer life to the entire mechanism.

Accordingly, it is seen that the present invention provides a counter drive mechanism which is relatively simple and inexpensive to produce and which provides a high level of efficiency and accuracy in operation. Moreover, the counter drive mechanism of the present invention consists of relatively few parts which are of relatively simple design and relatively simple to assemble. The simple but highly effective drive action permits a limited amount of overdrive to avoid injury to the parts and effectively prevents milking or falsifying the counts registered.

Having thus described the invention, I claim:

1. In a counter, the combination comprising a rotatably mounted pinion member having two axially adjacent portions each with a multiplicity of axially extending teeth spaced equidistantly about the periphery thereof, one of said portions having twice the number of teeth as the other portion with said teeth of said other portion being aligned with alternate teeth of said one portion; a number wheel member rotatably mounted with a toothed portion in meshing engagement with said one portion of said pinion member; a ratchet oscillatably mounted adjacent said pinion member with its axis of oscillation parallel to the axis of rotation of said pinion member, said ratchet having a generally curvilinear edge surface slidable upon the teeth of said other portion of said pinion member, said edge surface being configured for engaging a tooth of said pinion member and for rotating said pinion member in a direction counter to the direction of oscillation of said ratchet; means for oscillating said ratchet; and biasing means bearing upon said pinion member to urge rotation of said pinion member in a direction counter to the forward direction of oscillation of said ratchet, said biasing means bearing against a following edge of one of the teeth of said pinion member at all times when another of the teeth is not engaged by said ratchet curvilinear edge surface and for an additional period of time prior to disengagement of a tooth from said surface, said ratchet being oscillatable about an arc sufficient to rotate said pinion member at least to a point where said biasing means bears against the following edge of a tooth of said pinion member, whereby said biasing means urges a tooth of said pinion member into engagement with said curvilinear edge surface as said ratchet oscillates in a forward direction, said ratchet rotates said pinion member in a counter direction and disengages from the first tooth, and reengagement of said first tooth with said ratchet surface during oscillation of the ratchet in the reverse direction is prevented by said biasing means urging rotation of said pinion member in the direction counter to forward oscillation of the ratchet.

2. The counter of claim 1 wherein said means for oscillating said ratchet includesa driving member mounted for oscillation about an axis parallel to said ratchet axis and wherein means interengaging said ratchet and said driving member includes a slot in one of said members which has an elongated portion extending secantally outwardly and a substantially radially extending portion at the outer end of said elongated portion, the other of said members having a stud extending laterally from a point on said member spaced from the axis thereof into sliding engagement within said slot. 1

3. The counter of claim 2 wherein said counter is provided with limiting means for restricting the arc of oscillation of said driving member to minimize the tendency for damage from overdrive.

4. The counter of claim 1 wherein said ratchet mem-ber curvilinear edge surface has a recess therein for receiving and engaging a tooth of said pinion member during a portion of its oscillatory motion.

5. The counter of claim 1 wherein said biasing means is a fiat spring having one end fixedly mounted and its other end free and bearing tangentially against said other portion of said pinion member.

6. The counter of claim 1 wherein said number wheel member has a first element having the numerical indicia spaced about the circumference thereof, a second element with teeth spaced about the circumference thereof in meshing engagement with said one portion of said pinion member, and means disengageably connecting said first and second elements for driving said first element in the forward direction but preventing rotation in the other direction.

7. The counter of claim 1 wherein said means for oscillating said ratchet includes a driving member mounted for oscillation about an axis parallel to the axis of said ratchet and wherein means interengaging said ratchet and said driving member includes a slot in one of said members and a stud on the other of said members extending into sliding engagement within said slot, wherein said ratchet member curvilinear edge surface has a recess therein for receiving and engaging a tooth of said pinion member during a portion of its oscillatory motion, said biasing means urging an untoothed portion of said pinion member against the curvilinear edge surface of said ratchet during further oscillation of the driving member in the forward direction and during oscillation of the driving member in the reverse direction.

8. In a counter, the combination comprising a rotatably mounted pinion member having two axially adjacent portions each with a multiplicity of axially extending teeth spaced equidistantly about the periphery thereof, one of said portions having twice the number of teeth as the other portion with said teeth of said other portion being aligned with alternate teeth of said one portion; a number wheel member rotatably mounted with a toothed portion in meshing engagement with said one portion of said pinion member; a ratchet rotatably mounted adjacent said pinion member with its axis of oscillation parallel to the axis of rotation of said pinion member, said ratchet having a generally curvilinear edge surface slidable upon the teeth of said other portion of said pinion member with a recess therein for receiving and engaging a tooth of said pinion member during a portion of its oscillatory motion to impart rotation of said pinion member in a direction counter to the direction of oscillation of said ratchet; means for oscillating said ratchet including a driving member mounted for oscillation about an axis parallel to said ratchet axis and spaced therefrom and means interengaging said ratchet and driving member, said interengaging means including a slot in one of said members and a stud on the other of said members slidably engaged in said slot; and spring means bearing against said other portion of said pinion member to urge rotation of said pinion member in a direction counter to the forward direction of oscillation of said ratchet, said spring means bearing against a following edge of one of the teeth of said pinion member at all times when another of the teeth of said other portion is not engaged in said recess of the curvilinear edge surface and for an additional period of time prior to disengagement of a tooth from said recess, said ratchet be ing oscillatable about an arc sufficient to rotate said pinion member at least to a point where said spring means bears against the following edge of a tooth of said pinion member whereby said spring means urges a tooth of said pinion member into engagement within said recess as said ratchet oscillates in a forward direction, said ratchet rotates said pinion member in a counter direction and disengages from the first tooth, and reengagement of said first tooth within said recess during oscillation of the ratchet in the reverse direction is prevented by said spring means urging rotation of the pinion member in the direction counter to forward oscillation of the ratchet.

9. The counter of claim 8 wherein said counter is provided with limiting means for restricting the arc of oscillation of said driving member to minimize the tendency for damage from overdrive.

10. The counter of claim 8 wherein said slot has an elongated portion extending secantally outwardly across an imaginary line drawn between the axes of said ratchet and driving member and a substantially radially extending portion at the outer end of said elongated portion.

11. The counter of claim 8 wherein said spring means is a flat spring having one end fixedly mounted and its other end free and bearing tangentially against said other portion of said pinion member.

References Cited UNITED STATES PATENTS 1,192,193 7/1916 Har-t 235-117 1,506,939 9/1924 Pankonin 23511 7 1,566,628 12/1925 Stosick 235-117 2,572,784 10/1951 Van Veen 235--117 2,870,962 1/1959 Klein 235-117 STEPHEN J. TOMSKY, Primary Examiner.

S. A. WAL, Assistant Examiner.

U.S. Cl. X.R. 23591 

